1. Field Of The Invention
The present invention relates to a semirigid floating pavement with special application for new road surfacing.
2. Background
Road pavement techniques have a broad bibliography and very complete and improved studies for dimensions of surfaces with generally known or supposed hypotheses of calculation, such as density of traffic, axle load and features of the floor onto which it is being constructed.
The same is not true with respect to paving large surfaces for handling and transport of merchandise, especially solid bulk and containers particularly when there are to be paved grounds near the seaside. We wish herein to treat road surfaces as zones pertaining to ports and generally directed to areas filled to capacity such as those that exist with ports in expansion which create serious problems in moving seaboard freight towards the interior of a country, so that new docks have to be created, as well as large surfaces for the storage and manipulation of goods and freight onto artificial fillings. For example, at this time in Japan artificial islands are put up in industrial and commercial areas.
To come closer to the subject and concentrate on the necessities of an ideal hypothetical surface, we shall analyze the effects actually produced on pavements near the ports.
The heavy machinery actually circulating in the ports can surpass even 80 Tm per axle. Such heavy machinery can be loading shovels or equipment for containers which produce braking and turning effects on the proper ground and can increase the pressure on the pavement, thereby degrading the contact surface.
On the other hand, the arbitrariness of movement on the pavement acts unfavorably and makes the effects mentioned above possible on any point. Perhaps the worst effects could be avoided by ordering operations within one zone, which may be possible in some cases, and there could be oversized roller track paths. Although it would always be a zone hypothecated for any other change of order or treatment, it could be introduced within a medium or long time.
Due to the previous circumstances, use of rigid or non-rigid pavement is projected with certain skepticism knowing that in the end rigid pavements crack and break as a consequence of ground deformation and non-rigid pavements get deformed under the effects of load and settling on the ground, degrading the surface under the effect of pneumatic friction and other metallic elements impacting against the surface which also produce breakage.
As a consequence of what we discussed above and as a lesser evil (as explained in the latest publications about this particular subject), the actual trend in the U.S. and the U.K. is to treat these sorts of surfaces with prefabricated elements, a kind of paving block or stone, disposed in very diverse ways, knowing that the deformations which unavoidably will be produced in the pavement have to be repaired by raising the affected area, filling up the produced concavity and repaving, since a deformed surface is a great danger for the stability of the machinery and wares stored in movements of a certain height.
Anyway and as a prudent step, any type of pavement has as a premise the wait of five to ten years (once the filling-up phase is finished) for its execution, basically depending from the height of the filling and the quality (some times very expensive) of the material used, all to accomplish compactness in the filling and to avoid disastrous effects in the pavement as a consequence of large settlements or slumps.
Accordingly, it seems logical to think that a pavement with the above-identified qualities would improve the final result. Therefore, a pavement capable of supporting the mentioned changes (the non-rigid one being unsuitable for this purpose) which is capable of being formed according to the support onto which it is located (for which the rigid one is unsuitable), and which is capable of recovering its initial state once deformed (for which purpose prefabricated stone is unsuitable) brings forth some appreciable advantages, for instance, not waiting such a long time for a pavement of filling, using lower quality products for filling, with the consequent economic savings which in some cases could suppose and create a multi-use area, and without special conditioning.